Disc grinders



Dec. 11, 1956 LASKER 2,773,335

DISC GRINDERS Filed Jan." 25, 1954 I N VENTO EL ,WAr

B ADOLPH HAL/151452.

DISC GRINDERS Adolphe H. A. Lasker, Winnipeg, Manitoba, Canada Application January 25, 1954, Serial No. 405,960 1 Claim. (Cl. 51-173 My invention relates to new and useful improvements in disc grinders, the principal object and essence of my invention being to provide a device of the character herewithin described in Which there is a positive squeeze action engagement of the stone with the disc thus giving complete control of the stone pressure against the edge of the disc at all times.

A further object of my invention is to provide a device of the character herewithin described which is particularly safe in operation, inasmuch as the operator is some four feet from the revolving discs.

Another object of my invention is to provide a device of the character herewithin described which is adaptable to all types of discs now in use.

A still further object of my invention is to provide a device of the character herewithin described which is easily reversible so that the stone can be used to sharpen left or right handed discs.

A yet further object of my invention is to provide a device of the character herewithin described in which the stone can be used either vertically or horizontally as desired.

Still another object of my invention is to provide a device of the character herewithin described in which the castoring wheel automatically aligns with the concavity of the disc and thus forces the stone into position and engagement, so that the grinding pressure is controlled.

Yet another object of my invention is to provide a device of 'the character herewithin described which is simple in construction, economical in production, and

otherwise well suited to the purpose for which it is designed.

With the foregoing objects in view, and such other objects and advantages as will become apparent to those skilled in the art to which this invention relates as this specification proceeds, my invention consists essentially in the arrangement and construction of parts all as hereinafter more particularly described, reference being had to the accompanying drawings-in which: 1

Figure 1 is a top plan view of my device. 7

Figure 2 is an enlarged rear sectional view of the framework and supporting structure with the handle and stone removed for clarity.

Figure 3 is a front elevation of my device with the handles removed, but with the stone shown in the vertical position.

Figure 4 is a side elevation of my device with the stone The device hereinafter to be described is primarily designed for use in sharpening cultivating discs in which the discs themselves are revolved by a remote source of power and the grinding stone oifered up to the edge of the discs, but the novel squeeze action of my invention is adaptable to grinding devices which, in themselves, are rotatable.

Fired States Patent be mounted as shown in Figure 3, so that the wheel is The majority of disc grinders designed for the sharpening of cultivating discs suffer from the disadvantage that the entire grinding assembly has to be offered up to the edges of the disc, with the operator standing relatively close to the disc. These devices suifer from the disadvantages that accurate control of the pressure and location of the grinding wheel to the edge of the disc is extremely difficult, as well as the closeness of the operator to the disc, leading to the danger of injury to the operator.

My device overcomes both of these disadvantages, as will hereinafter be described, and as well provides a grinder which is adaptable for use with either left or right handed discs with very little change being required.

Proceeding now to describe my invention in detail, reference should first be made to Figure 5 in which a gang of'discs 1 is illustrated and adapted to be revolved by means of belt 2 extending around the end disc 3 and connected to a remote source of power (not illustrated) which may be the power take-01f from a tractor or a stationary engine.

My device collectively designated 4 consists of a triangular base 5 including a rear member 6, and a pair of forwardly converging members 7, terminating in a common apex 8, these members being made preferably from angle iron to afford a relatively stable base.

Supporting framework collectively designated 9 extends upwardly from a braced member 10 extending from the apex 8 to a point intermediate the ends of rear member 6. Said supporting framework consists of the central standard 11 formed preferably from angle iron and a cross piece or member 12 secured intermediate the ends thereof to the upper end of said member 11. A handle 13, angulated as at 14, is secured adjacent the upper end of member 11, said handle extending upwardly and rearwardly from the framework, as clearly shown in Figure 4.

An abrasive wheel 15 is secured to a spindle 16 which in turn is journalled for rotation within a bearing 17 secured to the distal end 18 of a wheel carrying bracket 19. Said bracket is right angulated at the inner end thereof as at 29 and is adapted to be secured to the side 21 of the cross piece 12 by means of bolts, it being seen that there are three apertures 22 provided in the end 21 of the cross piece 12 so that the bracket 19 may be mounted as shown in Figure 4, in'which case the abrasive wheel is adapted to revolve in a horizontal plane or, alternatively, it may adapted to revolve in a vertical plane.

An acute angled bracket 23 is secured by bolts 24 to the opposite side 25 of the cross piece 12, which once again is provided with three apertures 26, the which will hereinafter be described.

Means are provided cooperating with the abrasive wheel in order to control the engagement of same with the associated disc, and take the form of. a handle or lever 27 pivoted intermediate the ends thereof to the upper ilange28 of the ,afore-mentioned bracket 23, said pivot taking the form of a pin 29. The distal end 30 of the handle 27 is angulated through ninety degrees and a castoring wheel 31 is secured to this distal end and extends toward the abrasive wheel 15.

In operation, the discs 1 are caused to revolve by means of the belt 2, whereupon the device is positioned by means of the handles 13 and 27 so that the abrasive wheel 15 is adjacent the edge of the disc 1 to be sharpened.

Handle 27.is then moved apart from handle 13 thus purpose of accurate sharpening to take place. Furthermore, it Wlli be observed that the operator is situated some distance from the disc, thus adding substantially to the safe operating of the device. 7 t

It has previously been explained how the abrasive Wheel 15 can be mounted horizontally, as shown in Figures 1, 4

' and 5, so that the perimeter 15' thereof may be utilized.

Alternatively, the wheel may be situated as in Figure 3, so that the side face of same may be used.

However, it will also be noted that the brackets 23 and 19 are inter-changeable, thus permitting the device to be used on left or right handed discs, as desired.

Since various modifications can be made in my invention as hereinabove described, and many apparently widely different embodiments of same made within the spirit and scope of the claim without departing from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense.

What I claim as my invention is:

A friction driven sharpening device for cultivating discs, comprising a substantially triangular base, an upstanding T-shaped frame provided 011 said base and including a cross member having each end portion thereof provided with a set of three apertures, a pair of angle brackets having main arm portions overlying in spaced relation the apex portion of said base and angulated arm portions abutting said cross member, at least two fastening elements provided at spaced points on the angulated arm portion of each bracket and receivable selectively in each set of said apertures, a handle secured to said frame, an abrasive wheel rotatably mounted on the main arm portion of one of said brackets, a lever pivoted intermediate the ends thereof to the main arm portion of the other bracket and movable toward and away from said handle, and a disc-engaging castor wheel rotatably mounted on said lever adjacent said abrasive wheel, said apertures in each set being disposed in the pattern of a right-angled isoceles triangle and the spacing of said fastening elements on eachbracket corresponding to the length of each of two equal sides the triangular pattern, whereby said brackets may be fastened interchangeably to the opposite end portions of said cross member with the axis of said abrasive Wheel disposed selectively in horizontal and vertical planes.

References Cited in the file of this patent UNITED STATES PATENTS 1,343,342 Bray June 15, 1920 1,481,621 Neuman Jan. 22, 1924 2,185,519 Randall Jan. 2, 1940 2,510,601 Pater June 6, 1950 2,597,325 Hodges May 20, 1952 2,626,485 Waldbauer Jan. 27. 1953 

